Background: Various candidate vaccines against otitis media are currently in development. These include new or improved vaccines against non-typeable Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis, and respiratory syncytial virus. The ultimate success of otitis media vaccines will depend on their effectiveness and cost-effectiveness when implemented in large populations. Each of the possible vaccines and vaccination strategies poses a distinct set of tradeoffs in health benefits, risks, and costs. [unreadable] [unreadable] Research Plan and Specific Aims: We will develop a detailed decision analytic model to evaluate alternative otitis media vaccines and vaccination strategies for a hypothetical birth cohort of U.S. children. To complete this model, we will generate epidemiologic probabilities and costs by analyzing data from two ongoing cohort studies. We will assemble data from multiple additional sources and gather expert panel opinion where data are uncertain. The analysis will: 1) Compare the projected health benefits, health risks, and costs of alternative strategies for otitis media vaccination, including universal vaccination of infants between birth and 6 months, selective vaccination of children who are high-risk based on clinical history and/or sociodemographic factors, maternal immunization, and the status quo; 2) Define the sets of conditions under which otitis media vaccines are economically viable; and 3) Conduct sensitivity analyses to identify specific areas where further investment in research will yield information with maximum influence on future policy decisions. Projected Findings and Policy Implications: This study will provide population-based projections of the health and economic impact of alternative strategies for otitis media vaccination. The decision analytic model will yield information toward the optimal choices for current scientific inquiry, and will also provide a foundation for updated analyses as otitis media vaccines are further developed and tested. [unreadable] [unreadable]